APPENDIX 2: A BRIEF GUIDE TO WRITING IN CHEMISTRY



Similar documents
Formulas, Equations and Moles

Carolina s Solution Preparation Manual

Writing a Formal Lab Report

Enantiomers: Synthesis, characterization, and resolution of tris(ethylenediamine)cobalt(iii) chloride Introduction:

Chapter 16: Tests for ions and gases

IB Chemistry. DP Chemistry Review

Chapter 1: Moles and equations. Learning outcomes. you should be able to:

Stoichiometry Limiting Reagent Laboratory. Chemistry 118 Laboratory University of Massachusetts, Boston

Syllabus OC18 Use litmus or a universal indicator to test a variety of solutions, and classify these as acidic, basic or neutral

Chemical Reactions 2 The Chemical Equation

ANALYSIS OF ASPIRIN INFRARED (IR) SPECTROSCOPY AND MELTING POINT DETERMINATION

Experiment 3: Extraction: Separation of an Acidic, a Basic and a Neutral Substance

Chemical Reactions in Water Ron Robertson

PHYSICAL SEPARATION TECHNIQUES. Introduction

Separation by Solvent Extraction

The Synthesis of trans-dichlorobis(ethylenediamine)cobalt(iii) Chloride

ph: Measurement and Uses

Chapter Test B. Chapter: Measurements and Calculations

HOW TO MAKE STANDARD SOLUTIONS FOR CHEMISTRY

Unit 2: Quantities in Chemistry

Neutralizing an Acid and a Base

Prentice Hall. Chemistry (Wilbraham) 2008, National Student Edition - South Carolina Teacher s Edition. High School. High School

Experiment 8 - Double Displacement Reactions

ISOLATION OF CAFFEINE FROM TEA

Stoichiometry Limiting Reagent Laboratory. Chemistry 118 Laboratory University of Massachusetts, Boston

Review - After School Matter Name: Review - After School Matter Tuesday, April 29, 2008

Preparation of an Alum

Chemistry Post-Enrolment Worksheet

CHEMICAL REACTIONS OF COPPER AND PERCENT YIELD KEY

The Empirical Formula of a Compound

Chapter 8: Chemical Equations and Reactions

Calculation of Molar Masses. Molar Mass. Solutions. Solutions

Chemistry Assessment Unit AS 1

Lab 2 Biochemistry. Learning Objectives. Introduction. Lipid Structure and Role in Food. The lab has the following learning objectives.

Experiment 5. Chemical Reactions A + X AX AX A + X A + BX AX + B AZ + BX AX + BZ

Physical Changes and Chemical Reactions

EXPERIMENT 10 Chemistry 110. Solutions Part 2 ACIDS, BASES, AND ELECTROLYTES

experiment5 Understanding and applying the concept of limiting reagents. Learning how to perform a vacuum filtration.

SCH 4C1 Unit 2 Problem Set Questions taken from Frank Mustoe et all, "Chemistry 11", McGraw-Hill Ryerson, 2001

EXPERIMENT 12: Empirical Formula of a Compound

Chem 1100 Chapter Three Study Guide Answers Outline I. Molar Mass and Moles A. Calculations of Molar Masses

Chapter 3 Grammar and Punctuation

Writing and Balancing Chemical Equations

neutrons are present?

CHEM 2423 Recrystallization of Benzoic Acid EXPERIMENT 4 - Purification - Recrystallization of Benzoic acid

Lab #11: Determination of a Chemical Equilibrium Constant

Tutorial 4 SOLUTION STOICHIOMETRY. Solution stoichiometry calculations involve chemical reactions taking place in solution.

PURIFICATION TECHNIQUES

Stoichiometry. Lecture Examples Answer Key

Colorimetric Determination of Iron in Vitamin Tablets

Exampro GCSE Chemistry

Chemistry B11 Chapter 4 Chemical reactions

4.4 Calculations Involving the Mole Concept

Chapter 3: Stoichiometry

Chapter 3 Mass Relationships in Chemical Reactions

Coimisiún na Scrúduithe Stáit State Examinations Commission

Molarity of Ions in Solution

Determination of calcium by Standardized EDTA Solution

Santa Monica College Chemistry 11

Acid-Base Extraction.

General Chemistry Lab Experiment 6 Types of Chemical Reaction

Instructions Answer all questions in the spaces provided. Do all rough work in this book. Cross through any work you do not want to be marked.

IB Chemistry 1 Mole. One atom of C-12 has a mass of 12 amu. One mole of C-12 has a mass of 12 g. Grams we can use more easily.

5. Which temperature is equal to +20 K? 1) 253ºC 2) 293ºC 3) 253 C 4) 293 C

CHM1 Review for Exam 12

Unit 9 Compounds Molecules

Question Bank Electrolysis

Acid 7 Base. 1. Describe two things hydrochloric acid does in your body system. 2. What does sodium hydrogencarbonate do in your body system?

Austin Peay State University Department of Chemistry Chem The Use of the Spectrophotometer and Beer's Law

(1) e.g. H hydrogen that has lost 1 electron c. anion - negatively charged atoms that gain electrons (1) e.g. HCO 3 bicarbonate anion

Chemistry Ch 15 (Solutions) Study Guide Introduction

Green Principles Atom Economy Solventless Reactions Catalysis

2.02 DETERMINATION OF THE FORMULA OF A COMPLEX BY SPECTROPHOTOMETRY

General Chemistry I (FC, 09-10) Lab #3: The Empirical Formula of a Compound. Introduction

W1 WORKSHOP ON STOICHIOMETRY

CHEMICAL DETERMINATION OF EVERYDAY HOUSEHOLD CHEMICALS

Acids, Bases, and ph

SOLUBILITY OF A SALT IN WATER AT VARIOUS TEMPERATURES LAB

EXPERIMENT 5. Molecular Absorption Spectroscopy: Determination of Iron With 1,10-Phenanthroline

Chapter 4 Chemical Reactions

6 Reactions in Aqueous Solutions

Coimisiún na Scrúduithe Stáit State Examinations Commission

Chem101: General Chemistry Lecture 9 Acids and Bases

Chemistry 65 Chapter 6 THE MOLE CONCEPT

HOMEWORK 4A. Definitions. Oxidation-Reduction Reactions. Questions

Stoichiometry. What is the atomic mass for carbon? For zinc?

Experiment 8 Synthesis of Aspirin

Student Writing Guide. Fall Lab Reports

Sample Exercise 3.1 Interpreting and Balancing Chemical Equations

Candidate Style Answer

Phenolphthalein-NaOH Kinetics

Recovery of Elemental Copper from Copper (II) Nitrate

Solubility Curve of Sugar in Water

Name: Class: Date: 2 4 (aq)

Concept 1. The meaning and usefulness of the mole. The mole (or mol) represents a certain number of objects.

Getting the most from this book...4 About this book...5

OXIDATION-REDUCTION TITRATIONS-Permanganometry

Experiment 2: Recrystallization & Melting Point

SUCRALOSE. White to off-white, practically odourless crystalline powder

Format for Experiment Preparation and Write-Up

Transcription:

Writing Guide - 1 APPENDIX 2: A BRIEF GUIDE TO WRITING IN CHEMISTRY This document is a guide to assist students in chemistry courses with writing and formatting laboratory reports and research reports. An important goal of the Department is for our students to organize and communicate research results effectively and to write with acceptable scientific style. We hope that by providing many of the common stylistic, grammatical and organizational points in this single document, student can use this advice throughout their study of chemistry. A. Formatting a Report Layout. Use 12 point Times New Roman font and double spacing to allow space for comments and corrections. Number all pages, including those in appendices. Organization. A standard lab report or research paper should be formatted with sections. 1. TITLE. List the title of the experiment or meaningful name for your research report. This is followed by your name and the date submitted. If you worked with partners, list their names next to yours, but put an asterisk after your name* to indicate that you wrote the report. 2. ABSTRACT. The abstract should be able to stand alone. This means that someone should be able to read only your abstract and understand the basic nature of your report. For this reason, a good abstract clearly identifies the purpose of the experiment and the important results. Repeat: a good abstract contains a summary of your results. Avoid pedagogical comments such as this experiment helped us learn about the nature of chemical reactions or the goal of this experiment was to learn about dyes. Although those ARE important aspects and goals of the lab experience, the lab/research report should focus only on the data and results. Avoid starting your abstract with The purpose of this experiment was... Background information on the theory or applications of your experiment belongs in the Introduction section. Avoid referencing any other sources or parts of the report, because the abstract should be able to stand alone. Be specific about what was done: name the reagents or types (not models) of instruments that were used, the products of a reaction, numerical values that were measured or calculated, etc. Avoid vague statements such as "a metal complex was prepared and the percent yield was calculated." A better abstract would read "hexaammine cobalt(iii) chloride was prepared from cobalt (II) chloride, ammonia, ammonium chloride and hydrogen peroxide. The yield was 8.45 g (64 % based on cobalt)." The best way to learn how to write a good abstract is to READ some published abstracts. These can be found in chemistry journals (for example, The Journal of the American Chemical Society) which are in the library.

Writing Guide - 2 TIP: When writing a full report, write the Abstract last. 3. INTRODUCTION. The introduction section explains to the reader what basic scientific question is being addressed. It includes general background material or a brief historical perspective on the topic being investigated. It presents brief summaries, with references, of previous work. An effective introduction funnels the reader from a larger area of research, through examples of progress in the field to a clear statement of the research problem or approach being addressed in the current report. 4. EXPERIMENTAL. This section includes a description of your experimental procedure, and names of instruments used. For lab courses, the procedure can simply reference the lab manual, listing any changes to the published procedure. DO NOT REWRITE THE LAB MANUAL. For advanced labs or independent research, the experimental section should provide all the necessary detail for someone to be able to reproduce your work. Often, an Experimental section is subdivided into Materials (sources and purity of reagents used), Preparation of Compounds (with procedure, and summary of characterization by NMR, IR, UV-Vis spectroscopy, melting point, chromatography, or elemental analysis) and Instrumentation (manufacturer, description of any adaptation or sample preparation) sections. Consult JACS to see examples of Experimental sections for various types of reports. TIP: a good experimental section should allow another person, using what you have written and a lab manual, to completely reproduce what you did in the lab. 5. RESULTS & DISCUSSION. (may be single or separate sections) The Results should include a summary of your raw data (preferably in tabular form) and important observations. Do NOT include long tables of raw data; for those experiments simply present the results of your calculations. Calculations may be included in this section or in an Appendix, and a description of equations used in your calculations must be presented. Handwritten calculations are acceptable for lab reports. A Discussion section should take the form of an analysis of your results. Comment on the purpose of the experiment. What do the results indicate? What are sources of error (experimental uncertainty/precision)? What additional experiments could help address any dangling ends? Do the results agree with what others have found? Do the results support a model or hypothesis? For some lab courses, you can use this section to answer any questions presented in the manual or in class. Although you should answer the questions in the lab manual, this section should have the style of flowing prose, not simply answers to numbered questions. 6. CONCLUSION. Summarize your results and discussion with a short conclusion that is more than simply a reiteration of your results. Phrase it in terms of the broader questions addressed in the Introduction. 7. REFERENCES. Citations of the literature used in the previous sections (see section F)

Writing Guide - 3 8. APPENDIX. Graphics may appear here, along with lengthy calculations or additional material not needed when reading through the report. Graphics. Graphics include Tables, Figures, Schemes and chemical structures. Tables are columns of measured and/or calculated values or observations. All quantities should have units and be expressed using proper significant figures and scientific notation. Important experimental conditions should be listed as footnotes, especially when the table includes data obtained under different experimental conditions. Figures include: spectra, graphs, cartoons of experimental set-up or other drawings intended to show an object. Schemes include: reaction mechanisms, experimental flow charts or other drawings that are intended to show a process. All Tables, Figures and Schemes should be numbered sequentially and must be mentioned in the text. All graphics should be a full page in size and included at the end of the manuscript in the Appendix. Chemical structures can appear in the text and should be labeled with the same name, formula or compound number that appears in the text. B. Sentence Structure and Writing Style 1. Beginning a sentence. Avoid beginning a sentence with a symbol, numeric value or equation. in in 315.6 mg of ammonium chloride was added to the solution, which was then heated to 50 C. After the addition of 315.6 mg of ammonium chloride, the solution was heated to 50 C. ν is both the vibrational frequency and the IR radiation frequency. The frequency ν refers to both the vibrational frequency and the frequency of IR radiation. 2. Dangling Modifiers and Illogical Construction. Check that a modifier phrase or the pronoun it actually refers to the intended subject. (see also: subject-verb agreement.) in Being coated with grease, I cleaned the flask before adding reagents was I coated with grease or was the flask? Because the flask was coated with grease, it was cleaned before... in After transferring to a larger flask, the solution was heated to a boil. did the solution transfer itself? The solution was transferred to a larger flask and heated to a boil. in A diagram of the influenza virus is now available. To obtain it, contact the instructor. The instructor is making the influenza virus available? A diagram of the influenza virus is now available from the instructor.

Writing Guide - 4 in To prevent decomposition, the reaction flask must be purged of air. does the flask want to prevent decomposition? To prevent decomposition, purge all air from the reaction flask. 3. Equations. Equations typically appear as a separate line from the text and are numbered sequentially throughout the manuscript. Equations can then be referred to by number. example: The quenching rate constant can be calculated using the Stern-Volmer equation: Φ 0 /Φ q = 1 + k q τ 0 [Q] (2) 4. Hyphens. Hyphenate compound adjectives. 5-mL aliquots were added but, aliquots of 5 ml were added crystal deposited from the slowly-cooled solution. 5. Spaces. There should be a space between a quantity and its units and between a quantity or word and subsequent parenthetical phrase. 6.626 J s 25.15 K = 298.15 C 45 ml 456 nm (34,000 M -1 cm -1 ) 6. Personal Pronouns. By tradition, scientists avoid using the personal pronouns I and we and you in most technical communications. The use of third person instead of first person is preferred when reporting results. (see also: active voice) first person: I heated the solution at 100 C for 1 h. and I noticed that it turned blue. third person: When heated at 100 C for 1 h., the solution turned blue. 7. Pedagogical comments. Avoid including pedagogical comments in a report or scientific communication. Phrases such as this experiment helped us learn about the nature of chemical reactions or the goal of this experiment was to learn about dyes are addressing the process of learning not the science of the experiment. Although those ARE important aspects and goals of the lab experience, the lab report should focus only on the data and results. Also, try to avoid starting your abstract with "The purpose of this experiment was... 8. Personification. Molecules and equipment are not people, so do not personify them in your writing. in Sugar really wants to dissolve in water.

Writing Guide - 5 Sugar is very soluble in water. in Sodium wants to lose one electron to form Na +. Oxidation of Na to Na + is thermodynamically favorable. in The spectrum shows two bands of equal intensity Two bands of equal intensity appear in the spectrum. 9. Plural nouns. Data is plural for datum, spectra is plural for spectrum, phenomena is plural for phenomenon, and formulae is plural of formula. The amount of chemical reagent is singular, so use the correct verb tense. in in Data was acquired and a spectra is in the appendix. Data were acquired and a spectrum is in the appendix While the solution boiled, 5.0 g of KBr were added. While the solution boiled, 5.0 g of KBr was added. 10. Prepositions. Don t forget of between quantities and substance name. in... and 10 ml MeOH was added.... and 10 ml of MeOH was added. 11. Redundant or unnecessary phrases (pleonasm). in A photon of light having a wavelength of 530 nm... if not of light, what was the photon made of? Light having a wavelength of 530 nm... in In this experiment, aspirin was prepared from oil of wintergreen. If not this experiment, then in which experiment? Aspirin was prepared from oil of wintergreen. 12. Subject-verb agreement. Are you stating that an inanimate object is drawing a conclusion, or suggesting a strange cause and effect? (see also: dangling modifers) in The IR spectrum implies that water is in the aspirin sample. (spectra don t imply, people do) The presence of water in the aspirin sample is inferred from the IR spectrum. in Water was present in the aspirin product because of the peak at 3200 cm -1 in the IR spectrum. (the peak in the spectrum didn t cause water to be present) The peak at 3200 cm -1 in the IR spectrum indicates that water was present in the aspirin product. (water caused the peak in the spectrum)

Writing Guide - 6 C. Verbs 1. Active voice. By avoiding personal pronouns, scientists often depend excessively on the passive voice, which can weaken the writing style. When possible, replace passive voice with active voice. passive voice: active voice: passive voice: active voice: A vapor was observed when the solution was heated. A vapor formed above the hot solution. There was some solid that did not dissolve. Some solid did not dissolve. 2. Subject-verb agreement. Based on whether the subject is singular or plural, use the correct verb tense. A quantity used is a singular subject, even when that quantity is in a plural form of units. in 12 g were added 12 g was added 3. Verb tense. Past tense is used to describe a procedure that you followed in an experiment. Present tense is used to describe a scientific fact, such as the properties of a molecule. Hydrochloric acid was added to the flask slowly in order to prevent decomposition of the product. Hydrochloric acid is a caustic substance that must be used with caution. 4. Verbing a Noun. Don t turn nouns into verbs. in ammonia complexes to cobalt ions ammonia forms complexes with cobalt ions. in the mixture was centrifuged to separate the solid. The solid was separated from the mixture using a centrifuge. in The solution was rotovapped to dryness The solvent was removed by rotary evaporation D. Abbreviations, Formulae and Numerals 1. Standard Abbreviations. Use standard JACS abbreviations (note: not all journals use exactly the same abbreviations: ml = milliliter; μg = microgram; nm = nanomolar h = hour; min = minute; s = second K = degrees Kelvin, C = degrees Celsius

Writing Guide - 7 2. Chemical Formulae. Use subscripts, superscripts, parentheses, and symbols appropriately in chemical formulae. Cr 3+ (aq) K 2 [PtCl 4 ] [Ru(bpy) 3 2+ ](PF 6 ) 2 3. Compound Numbers. Compounds can be numbered if repeated long compounds names become cumbersome. The number should be defined (usually in bold or underlined) somewhere early in the manuscript, often when it is first presented. The numbers should appear in parenthesizes when used as adjectives, but not when used as nouns. example: Investigations into the fluorescence of 8-hydroxyquinoline (1), 4-iodo-8- hydroxyquinoline (2) and 2-methyl-4-iodo-8-hydroxyquinoline (3) are described in this paper. Recrystallization of 1 and 2 afforded analytically pure samples, but vacuum sublimation of the methyl derivative (3) was necessary to remove fluorescent impurities. 4. Decimal Places. For values less than unity, use a leading zero. Avoid writing values having too many zero; use scientific notation. 0.15 μl not.15 μl 2.3 x 10-5 M not 0.000024 M 5. Defining Abbreviations. Abbreviations for chemical compounds, ligand, instruments or methods should be defined in the text before using throughout the manuscript. The complex cation Ru(bpy) 3 2+, where bpy = 2,2 -bipyridine, is luminescent... Surfactants such as sodium dodecyl sulfate (SDS) lead to lower drag... Peptide structures were minimized using the empirical force filed (EFF) method. The American Chemical Society (ACS) sponsors two annual national meetings. 6. Organic Abbreviations. Standard organic abbreviations can be used in text and formulae. Me = methyl Et = ethyl ipr = iso-propyl tbu = tert-butyl Ch cyclohexyl 7. Reagents and Solvents. Use chemical formulae for standard reagents and solvents, but not when the name is shorter or more precise

Writing Guide - 8 NaOH (aq) in place of sodium hydroxide H 2 SO 4 (aq) in place of sulfuric acid CH 2 Cl 2 in place of dichloromethane caffeine in place of C 8 H 10 N 4 O 2 E. Chemical Terms and Expressions 1. Chemical names. The names of chemicals are not capitalized, unless they are trade names such as Tylenol or Viagra. in The reaction of aqueous Cobalt(II) with Aspirin was investigated. The reaction of aqueous cobalt(ii) with aspirin was investigated. 2. Create. Chemistry involves synthesizing new compounds, preparing solutions, characterizing products. Avoid using phrases such as products were created. Too divine. 3. Measurements. Spectra are measured with or using a spectrometer, not on a spectrometer (ouch!) 4. Machines. Spectrometers (UV-Vis, IR, NMR, etc.) are instruments, not machines. 5. React. As an intransitive verb, react should not have an object and should not have a passive voice. Chemical reagents react with each other, they are not reacted. in Potassium hydroxide and hydrochloric acid were reacted to produce water and potassium chloride. The reaction of potassium hydroxide and hydrochloric acid produced water and potassium chloride. 6. Tested. A hypothesis can be tested and a student can be tested. For most laboratory work, the terms measured, investigated, determined, calculated or obtained often work better. in The absorbance of the solution was tested using the UV-vis machine. The absorbance of the solution was measured using a UV-vis spectrophotometer.

Writing Guide - 9 F. References There are numerous styles for formatting references. Unless otherwise instructed, citations should be formatted in the JACS style and appear as endnotes. Alternatively, article titles can also be included. Most important is to prepare citations with a uniform style. Last name, initials; Last name, initials Journal Title year, volume (issue), starting page. or Last name, initials; Last name, initials Article Title Journal Title year, volume (issue), starting page. Schlabach, M.; Limbach, H.-H.; Shu, A.; Bunnenberg, E.; Tolf, B.; Djerassi, C. J. Am. Chem. Soc. 1993, 115, 4554. Additional Materials for Writing Lab/Research Reports Davis, Martha Scientific papers and presentations San Diego : Academic Press, 1997 Dodd, Janet S. (ed.)the ACS style guide : a manual for authors and editors ACS, 1997. Eisenberg, Anne Strategies five productive chemists use to handle the writing process. J. Chem. Educ. 1982, 59, 566. Potera, Carol The Basic Elements of Writing a Scientific Paper: The Art of Scientific Style J. Chem. Educ. 1984, 61, 247. Spector, Thomas Writing a Scientific Manuscript: Highlights for Success J. Chem. Educ. 1994, 71, 47. "To avoid criticism, do nothing, say nothing, be nothing." -Elbert Hubbard